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Disassembling the Amazon Dash

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21–30 of 115 posts

Re: Disassembling the Amazon Dash

#21
Can anyone recommend any resources on power management on something like this?

My background in electronics is quite basic though I'd love to understand how they managed to build an ARM-based, battery-powered device that is predicted to last for years. I know it's not "always on" but it's fascinating nonetheless and I think building something similar would make for a fun project.

Re: Disassembling the Amazon Dash

#22
post #13

I'm disappointed that it isn't powered by the kinetic energy of the pressing: I heard some Philips Zigbee control devices work that way (but Wifi might be too power hungry for that). And I was expecting them to use the ESP8266 for this: Does anybody know if (at scale) that would have been cheaper?

[deleted]

Re: Disassembling the Amazon Dash

#23
post #21

Can anyone recommend any resources on power management on something like this? My background in electronics is quite basic though I'd love to understand how they managed to build an ARM-based, battery-powered device that is predicted to last for years. I know it's not "always on" but it's fascinating nonetheless and I think building something similar would make for a fun project.

Basically it always sleeps, and wakes only when you press the button - does it job rapidly and goes back to sleep.

Since you rarely press the button , it can live for years.

Re: Disassembling the Amazon Dash

#24
post #21

Can anyone recommend any resources on power management on something like this? My background in electronics is quite basic though I'd love to understand how they managed to build an ARM-based, battery-powered device that is predicted to last for years. I know it's not "always on" but it's fascinating nonetheless and I think building something similar would make for a fun project.

Most microcontrollers have extremely low power sleep states, maintaining interrupts on external inputs often only draws the smallest amounts of power. When you're designing for low power electronics like this you often run into the problem of the self discharge of the battery completely dwarfing any consumption your microcontroller has. I'm reasonably confident they chose a lithium AAA simply because they have very low self discharge, and a AAA over something like a coin cell due to the rather enormous amount of power needed to transmit 802.11.

I get the feeling that this device is pretty tentative for Amazon, they haven't gone to huge lengths to keep the price of the build down. In particular there's also a connector on the bottom right of the PCB that looks a lot like it could be for a small screen or some other peripheral.

Re: Disassembling the Amazon Dash

#25
post #20

Earlier quoted context omitted.

The microphone is only active when you hold down the button - if it's always on (for whatever reason, accidentally or maliciously), the unit would run out of power in a few hours, it's powered by a single AAA cell.

It doesn't have to be always on, it could be remotely controlled.

It's not powered up, though. That's why it lasts so long on one battery. The button wakes it up.

Re: Disassembling the Amazon Dash

#26
post #9

Why does amazon use a module,instead of certifying their own ? this hopes to be a large volume project , so the savings could be considerate.

To me, the choice to use off the shelf hardware reflects Amazon's dedication to lean values. In this sense, they're doing the absolute minimum (using off-the-shelf hardware instead of spending 2 years spinning their own SoC) to verify that their product (on-demand household commodity ordering) is actually something people want. Makes a lot more sense in terms of turnaround time and money - if the idea proves valuable, they can start expending the effort to reduce costs through SoC development.

As the top commenter pointed out, though, I don't think they would really need to spend the time recouping those margins - since all the brands signed up for this service are big-name brands owned by Proctor and Gamble, it could indicate a relationship wherein P&G helps them absorb some of the costs of the hardware in exchange for what is effectively marketing.

Re: Disassembling the Amazon Dash

#27
post #17

Is it just me that finds the entire concept of the Dash ridiculous? I mean, what's the idea, having a button for every single product we buy? And we need to set it up first. How is that any better than recurring ordering or just opening the website and ordering it? Are we expected to have an entire wall of dashes at our place? I guess we'll need to sort them alphabetically or by color, so we don't waste time searchin…

Or you know, why not a phone application that would order the same thing with a single tap.

Re: Disassembling the Amazon Dash

#28
post #7

One neat thing Amazon are doing with this product, which I hadn't considered as an "internet of things" option, is making each unit of hardware order a single supplier's goods. All the example buttons say "Tide" or "Bounty" or "Gillette" or "Olay" right on the button - all Procter & Gamble. And the other goods pictured [1] are all brand-name goods with fairly big marketing budgets. In the jargon of the grocery indust…

That's a really insightful strategy. Amazon wins by not needing to sink more development time into cheaper hardware by getting P&G to offset costs, while P&G wins by effectively pays a one-time fee per customer per product to ensure a steady stream of sales.

Hadn't thought of that angle at all. Enlightening comment!

Re: Disassembling the Amazon Dash

#29
post #13

I'm disappointed that it isn't powered by the kinetic energy of the pressing: I heard some Philips Zigbee control devices work that way (but Wifi might be too power hungry for that). And I was expecting them to use the ESP8266 for this: Does anybody know if (at scale) that would have been cheaper?

The ESP8266 has peak draws of almost a watt when transmitting, unless Amazon releases a crank-to-order device that doesn't seem particularly plausible. I'm slightly surprised that they didn't use the Espresso solution here to keep their part count down, but it is possible this model is just to gauge market interest.

Re: Disassembling the Amazon Dash

#30
post #7

One neat thing Amazon are doing with this product, which I hadn't considered as an "internet of things" option, is making each unit of hardware order a single supplier's goods. All the example buttons say "Tide" or "Bounty" or "Gillette" or "Olay" right on the button - all Procter & Gamble. And the other goods pictured [1] are all brand-name goods with fairly big marketing budgets. In the jargon of the grocery indust…

What if the Dash becomes very popular? I believe we'd see an explosion of companies funding dash buttons which would, in my opinion, be a bad thing for the customer. I don't like the idea of locking myself into a brand for the life of the device.

I'd like to see a configurable button that orders, say, the cheapest paper towels that have at least a 4-star rating. The suppliers probably wouldn't be happy about the competition though.

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